1. Field of the Invention
The present invention relates to a mounting structure for an engine cover which covers an engine.
2. Related Art
In engine compartments of automobiles in recent years, it becomes a general practice to provide an engine cover above an engine. This engine cover has functions to shield noise that has leaked from the engine (transmitted noise) and to improve the design properties of the interior of the engine compartment by preventing the sight of the engine.
The engine cover is generally mounted to the cylinder head cover of the engine. As this occurs, the engine cover is, in general, mounted to the cylinder head cover through a screw-fastening via bolts (see, for example, JP2001-98954A). Through holes are provided in the engine cover disclosed in JP2001-98954A, and threaded screw-fastening holes are provided in the cylinder head cover to which the engine cover is to be mounted at positions which correspond to the through holes so provided. Then, when the engine cover is mounted to the cylinder head cover, bolts are passed through the through holes from above the engine cover so as to be screwed into the threaded screw-fastening holes, so that the engine cover is mounted to the cylinder head cover by virtue of a fastening force exerted by the threaded screw-fastening holes and the bolts.
In the engine cover mounting structure like this, since the through holes are provided in the engine cover, the mounting work can be performed while confirming the position of the threaded screw-fastening holes through the through holes. Consequently, there is provided an advantage that the mounting work can be facilitated. In contrast, however, since the through holes in the engine cover remain visible from above the engine cover after the mounting of the engine cover, there is caused a problem that the design properties are deteriorated.
In addition, since the mounting of the engine cover to the cylinder head cover is implemented through the screw-fastening by the bolts, a gap between the cylinder head cover and the engine cover is governed by the length of the bolts, and there has been difficulty in setting the gap between the cylinder head cover and the engine cover to a desired size.
As a method for mounting the engine cover to the cylinder head cover by any other method than the screw-fastening one, there is considered a method in which fixing portions are provided on a lower side of the engine cover and portions to be fixed which are formed into a corresponding shape to that of the fixing portions are provided on an upper side of the engine cover, whereby the fixing portions and the portions to be fixed are fixed to each other through engagement or the like, so that the engine cover is mounted to the cylinder head cover. According to this method, even in the event that hole-like fixing portions are provided on the lower side of the engine cover, since these fixing portions do not have to be opened in the upper side of the engine cover, it is considered that a risk can be avoided that the fixing portions become visible from above the engine cover, whereby the engine cover can provide superior design properties.
In the method like this, however, since the fixing portions cannot be viewed from above the engine cover, the positions of the fixing portions and the portions to be fixed cannot be confirmed also when the engine cover is attempted to be mounted to the cylinder head cover. Due to this, the positioning of the engine cover at the mounting position becomes difficult, leading to a problem that the working efficiency of mounting work is deteriorated. In particular, in a case where a number of fixing portions are mouted to a corresponding number of portions to be fixed, since the positioning of each portion to be fixed needs to be implemented relative to each fixing portion, the positioning of the engine cover at the mounting position becomes more difficult, leading to a problem that the working efficiency of mounting work is deteriorated further.
Furthermore, in this case, a space for engagement of the fixing portions with the portions to be fixed is required between the cylinder head cover and the engine cover. Thus, this makes it difficult to set the gap between the cylinder head cover and the engine cover to a desired size, leading to, for example, a problem that the engine cover cannot be mounted to a position close to the cylinder head cover. In the event that the gap between the cylinder head cover and the engine cover is not set to a desired size, there may be caused a problem that the transmitted noise from the engine is not sufficiently shielded by the engine cover.